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Research on the Impact of Different Lymph Node Dissection Scopes on Postoperative Recurrence and Survival Rates in Patients with Early Gastric Cancer
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作者 Zhijun Mao Yingdi Wei +2 位作者 Ganjie Yang Pan Gao Tong Hui 《Proceedings of Anticancer Research》 2026年第1期130-137,共8页
Early-stage gastric cancer;Extent of lymph node dissection;D1 dissection;D2 dissection;Recurrence rate;Survival rateObjective:To investigate the impact of different lymph node dissection scopes on postoperative recurr... Early-stage gastric cancer;Extent of lymph node dissection;D1 dissection;D2 dissection;Recurrence rate;Survival rateObjective:To investigate the impact of different lymph node dissection scopes on postoperative recurrence and survival rates in patients with early gastric cancer,providing evidence-based support for optimizing clinical surgical plans.Methods:A retrospective analysis was conducted on the clinical data of 100 patients with early gastric cancer who underwent surgical treatment at our hospital from October 2021 to October 2023.Patients were divided into Group D1(n=50)and Group D2(n=50)based on the extent of lymph node dissection.Group D1 underwent limited lymph node dissection(dissection of the first station of lymph nodes around the stomach),while Group D2 underwent standard lymph node dissection(dissection of the first and second stations of lymph nodes around the stomach).Surgical-related indicators,the incidence of postoperative complications,the 2-year recurrence rate,and the 2-year survival rate were compared between the two groups of patients.Results:The operative time,intraoperative blood loss,postoperative hospital stay,and the number of lymph nodes dissected were significantly higher in the D2 group than in the D1 group(all P<0.001).The overall incidence of postoperative complications was higher in the D1 group than in the D2 group,but the difference was not statistically significant(χ^(2)=0.884,P=0.766).After a 2-year follow-up,the recurrence rate was significantly higher in the D1 group than in the D2 group(χ^(2)=4.000,P=0.046).The 2-year survival rate was significantly lower in the D1 group than in the D2 group(χ^(2)=5.005,P=0.025).A total of 100 patients with early-stage gastric cancer were grouped according to the depth of invasion,degree of differentiation,and lymph node metastasis status,and the recurrence rates of different subgroups were compared.The results showed that the recurrence rate was higher in patients with T1b stage than in those with T1a stage(χ^(2)=5.005,P=0.025),higher in poorly differentiated patients than in moderately and well-differentiated patients(χ^(2)=4.155,P=0.042),and higher in patients with lymph node metastasis than in those without lymph node metastasis(χ^(2)=4.512,P=0.034).Conclusion:Compared with D1 limited lymph node dissection,D2 standard lymph node dissection can significantly reduce the postoperative recurrence rate and improve the 2-year survival rate in patients with early-stage gastric cancer without significantly increasing the risk of postoperative complications.Although the surgical trauma is slightly greater,the overall prognosis is better,making it a preferred surgical treatment option for patients with early-stage gastric cancer. 展开更多
关键词 Early-stage gastric cancer Extent of lymph node dissection D1 dissection D2 dissection Recurrence rate Survival rate
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Microstructural modification and tailoring the shear mechanical properties of in-situ manufactured Mg-Si alloys via varying cooling rates during solidification
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作者 Fatemeh Asghari Mehdi Malekan +2 位作者 Hamed Mirzadeh Alireza Kalhor Massoud Emamy 《Journal of Magnesium and Alloys》 2026年第1期476-489,共14页
The influences of silicon addition to commercially pure magnesium(CP Mg)and cooling rate during solidification on the as-cast microstructure and shear mechanical properties of Mg-Si alloys were systematically investig... The influences of silicon addition to commercially pure magnesium(CP Mg)and cooling rate during solidification on the as-cast microstructure and shear mechanical properties of Mg-Si alloys were systematically investigated.For this purpose,the Mg-0.6Si,Mg-1.34Si,and Mg-3Si(wt%)alloys were considered as hypoeutectic,eutectic,and hypereutectic alloys,respectively.By decreasing the geometrical modulus of the solidifying section(increasing cooling rate),remarkable grain refinement,refining the dendrite arm spacing(DAS),and modification of Mg_(2)Si particles were achieved.Moreover,the grain size was refined via Si addition in the hypoeutectic range,while coarsening of grain size at high Si concentrations was observed.The results of shear punch testing and hardness measurements demonstrated that the ultimate shear strength(USS)and hardness increased by increasing the cooling rate during solidification.Moreover,Si addition generally improved hardness,while the highest USS level was achieved for the eutectic alloy due to the fine grain size and strengthening effect of the eutectic constituent.However,regarding the hypereutectic Mg-3Si alloy that exhibited high hardness,the shear properties were inferior due to the detrimental effect of the primary Mg_(2)Si particles.Finally,the results were discussed with consideration of the relationship between strength and hardness,for which the critical effect of Si was clarified. 展开更多
关键词 Mg-Si alloys SOLIDIFICATION Grain refinement Cooling rate Mechanical properties
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A GATED SERVICE SINGLE VACATION M/G/1 QUEUE SYSTEM WITH SETUP AND CLOSEDOWN TIMES AND DIFFERENT CUSTOMER ARRIVAL RATES
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作者 Ying SUN Zhanyou MA Tongyu XU 《Acta Mathematica Scientia》 2026年第1期407-426,共20页
A gated service single vacation M/G/1 queue with setup and closedown periods,and different customer arrival rates,is studied in this paper.The probability generating function of the number of systems for customers who... A gated service single vacation M/G/1 queue with setup and closedown periods,and different customer arrival rates,is studied in this paper.The probability generating function of the number of systems for customers who are at the initial moment of service period is analyzed by using a total probability theorem,and the stability condition of the system is obtained.The stationary distribution of the queue length is solved by the regeneration cycle method.The stochastic decomposition of queue length in the steady state is calculated,and the service cycle is obtained.Moreover,classified discussions are established in order to solve the steady-state distribution for the waiting time.The variation of system performance indicators with parameters is analyzed by performing numerical experiments. 展开更多
关键词 different arrival rates regeneration cycle method stochastic decomposition theorem stationary queue length
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Multi-scale quantitative study on cemented tailings and waste-rock backfill under different loading rates
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作者 YIN Sheng-hua CHEN Jun-wei +4 位作者 YAN Ze-peng ZENG Jia-lu ZHOU Yun YANG Jian ZHANG Fu-shun 《Journal of Central South University》 2026年第1期357-374,共18页
The development of metallic mineral resources generates a significant amount of solid waste,such as tailings and waste rock.Cemented tailings and waste-rock backfill(CTWB)is an effective method for managing and dispos... The development of metallic mineral resources generates a significant amount of solid waste,such as tailings and waste rock.Cemented tailings and waste-rock backfill(CTWB)is an effective method for managing and disposing of this mining waste.This study employs a macro-meso-micro testing method to investigate the effects of the waste rock grading index(WGI)and loading rate(LR)on the uniaxial compressive strength(UCS),pore structure,and micromorphology of CTWB materials.Pore structures were analyzed using scanning electron microscopy(SEM)and mercury intrusion porosimetry(MIP).The particles(pores)and cracks analysis system(PCAS)software was used to quantitatively characterize the multi-scale micropores in the SEM images.The key findings indicate that the macroscopic results(UCS)of CTWB materials correspond to the microscopic results(pore structure and micromorphology).Changes in porosity largely depend on the conditions of waste rock grading index and loading rate.The inclusion of waste rock initially increases and then decreases the UCS,while porosity first decreases and then increases,with a critical waste rock grading index of 0.6.As the loading rate increases,UCS initially rises and then falls,while porosity gradually increases.Based on MIP and SEM results,at waste rock grading index 0.6,the most probable pore diameters,total pore area(TPA),pore number(PN),maximum pore area(MPA),and area probability distribution index(APDI)are minimized,while average pore form factor(APF)and fractal dimension of pore porosity distribution(FDPD)are maximized,indicating the most compact pore structure.At a loading rate of 12.0 mm/min,the most probable pore diameters,TPA,PN,MPA,APF,and APDI reach their maximum values,while FDPD reaches its minimum value.Finally,the mechanism of CTWB materials during compression is analyzed,based on the quantitative results of UCS and porosity.The research findings play a crucial role in ensuring the successful application of CTWB materials in deep metal mines. 展开更多
关键词 cemented backfill waste rock loading rate multi-scale analysis mercury intrusion porosimetry pore structure MICROMORPHOLOGY
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Distinct Mechanisms Governing Two Types of Extreme Hourly Rainfall Rates in the Mountain Foothills of North China During the Passage of a Typhoon Remnant Vortex from 30 July to 1 August 2023 被引量:2
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作者 Rudi XIA Yuqing RUAN +8 位作者 Jisong SUN Xudong LIANG Chong WU Feng LI Ju LI Jinfang YIN Xinghua BAO Mingxin LI Xiaoyu GAO 《Advances in Atmospheric Sciences》 2025年第4期761-779,共19页
This study investigates extreme rainfall episodes along the eastern foothills of the Taihang Mountains in North China from 30 July to 1 August 2023.It focuses on two types of extreme hourly rainfall rates(HRRs),i.e.,t... This study investigates extreme rainfall episodes along the eastern foothills of the Taihang Mountains in North China from 30 July to 1 August 2023.It focuses on two types of extreme hourly rainfall rates(HRRs),i.e.,the maximum regionalaverage HRR and site-observed HRR,which exhibited sequential development over southern,middle,and northern key regions.These rainfall extremes occurred in an environment where a high-pressure barrier over North China prevented the intrusion of cold air masses from the north while a northward-moving typhoon remnant vortex and its associated low-level jet(LLJ)transported warm and moist airflow from the south.Two distinct echo evolution modes and convection initiation mechanisms are identified for the two types of extreme HRRs.The maximum regional-average HRR occurred when the LLJ arrived to the east of the key regions,while the maximum site-observed HRR occurred when the warmer vortex center influenced the regions.Taking the northern key region as a representation,at the time of the maximum regional-average HRR,slantwise ascent of the airflow along a warm-frontal-like boundary released energy related to symmetrical instability,resulting in stratiform rainfall with weak convective cores.The transport of locally initiated convection over the eastern plain region,where the atmospheric stratification was more potentially unstable,also significantly contributed.When the maximum site-observed HRR occurred,the terrain lifting of warm and moist southeast airflow led to intense convection over the mountain foothills.Overall,the passage of the warm-core typhoon remnant vortex and interaction with Taihang Mountains determined the timing and location of extreme HRRs across the key regions. 展开更多
关键词 extreme rainfall hourly rainfall rate MOUNTAIN VORTEX mechanism
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Drought tolerance traits explain differential stem growth rates of evergreen and deciduous trees in a tropical karst forest 被引量:1
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作者 Yu-Mei Yan Ze-Xin Fan +1 位作者 Pei-Li Fu Zhi-Yong Zhang 《Plant Diversity》 2025年第3期454-465,共12页
The karst forest in southwestern China is characterized by thin soil layers,numerous fissures and holes,resulting in low soil water availability and poor water retention,making it challenging for plant growth and surv... The karst forest in southwestern China is characterized by thin soil layers,numerous fissures and holes,resulting in low soil water availability and poor water retention,making it challenging for plant growth and survival.While the relationship between plant functional traits and tree growth performance has been extensively studied,the links between tree seasonal growth and drought-tolerant traits in tree species with different leaf habit remains poorly understood.This study evaluated the associations between four-year averaged rainy season stem diameter growth rate and 17 branch and leaf traits across evergreen and deciduous species in a tropical karst forest in southwest China.The cross-species variations in tree growth rates were related to plant hydraulic traits(e.g.,vessel lumen diameter,xylem vessel density,stomatal density,and stomatal size)and leaf anatomical traits(e.g.,total leaf thickness,lower/upper epidermis thickness,and spongy thickness).The growth of evergreen trees exhibited lower hydraulic efficiency but greater drought tolerance than deciduous tree,which enabled them to maintain higher persistence under low soil water availability and consequently a relatively longer growing season.In contrast,deciduous species showed no correlation between their functional traits and growth rate.The distinct water use strategies of evergreen and deciduous trees may offer a potential explanation for their co-existence in the tropical karst forests. 展开更多
关键词 Functional traits Growth rates Drought-tolerant Hydraulic conductivity Leaf anatomy traits Tropical karst forest
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Comparative Effects of Doses of Nauclea latifolia and 17 Alpha Methyltestosterone on Masculinization and Growth Rates of Tilapia Orechromis niloticus Larvae in Senegal
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作者 Mouhamadou Amadou Ly Fafanding Sane +3 位作者 Robane Faye Baboucar Sane Malick Aliou Sene Cheikh Tidiane Ba 《Open Journal of Applied Sciences》 2025年第1期1-12,共12页
One of the main obstacles to the development of aquaculture in Senegal is the availability of fry and juveniles in sufficient quantities. The objective of our study is to evaluate the effects of treatment with the hor... One of the main obstacles to the development of aquaculture in Senegal is the availability of fry and juveniles in sufficient quantities. The objective of our study is to evaluate the effects of treatment with the hormone 17 alpha methyl testosterone (17-&-MT) and different doses of Nauclea latifolia root powder on the masculinization rates of tilapia Oreochromis niloticus larvae in Senegal. A total of 450 larvae of Oreochromis niloticus, with an average size of 0.012 g, were placed in 15 aquariums, each containing 30 individuals and fed one of the 5 diets in triplicate. These individuals were fed either a diet containing a plant extract at a dose of 180 mg (T180), 200 mg (T200) and 250 mg (T250) per kg of food, or a diet containing 60 mg/kg of the hormone 17-&-MT (TMT), or a diet without either the plant extract or the hormone (T0). Individuals were fed for 30 days with the treatment diets, and then with the industrial feed for the rest of the experiment. At the end of the study, the results of the masculinization rate were: 80.49%, 73.13%, 69.23%, 66.67% and 45.95% for T250;T200, TMT, T180 and T0 respectively. In summary, we can say that the 250 mg/kg dose provides better masculinization, followed by 200mg/kg and then 17 α MT. For the plant, the increase in the percentage of males is dose-dependent. These results also translate into better growth of individuals in this order. However, the relatively lower survival rates observed in batches treated with Nauclea latifolia extract indicate that these treatments could have a deleterious effect on the survival of Oreochromis niloticus larvae. These results suggest the use of N. latifolia extract at a dose of 250 mg/kg feed for better production of male O. niloticus larvae without compromising their growth. 展开更多
关键词 Nauclea latifolia Masculinization rate Growth Performance Oreochromis niloticus
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An effective approach for correlating Na^(+) concentrations with sweating rates in wearable sweat sensing platform
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作者 Anwei He Xiaohe Wang +6 位作者 Liang Zhang Haolong Zhang Xingli Xu Chenyang Yu Yongquan Ma Wei Wei Pengfei Niu 《Nanotechnology and Precision Engineering》 2025年第1期58-67,共10页
Accurately correlating the sweating rate and the concentration of biomarkers in sweat is essential in many sweat-based diagnostic applications.These two measurements are always done simultaneously in wearable sweat se... Accurately correlating the sweating rate and the concentration of biomarkers in sweat is essential in many sweat-based diagnostic applications.These two measurements are always done simultaneously in wearable sweat sensing platforms.However,concentration measurements of biomarkers are always delayed on the timeline compared with their production,whereas there is no such delay for sweating rate.Thus,a timeline mismatch exists between these two measurements.This means that the concentration vs rate correlation constructed on the basis of such measurements will deviate from the actual correlation.This study demonstrates the existence of this mismatch and explains its cause using sweat Na^(+)measurements.It also proposes an effective approach that applies a point-by-point compensation for the delay between Na+measurements and the real-time sweating rates,such that the data on the repositioned concentration vs time curve correspond to exactly the same point on the timeline as their production.A vison sensor is developed to measure the sweating rate with high accuracy at a frequency of more than 0.1 Hz.Off-body and on-body measurements of sweating rate and Na^(+)concentration are carried out,and concentration–rate correlations are constructed using both measured and repositioned concentration curves.The least squares and random forest methods are employed to fit the constructed correlations and evaluate the reliability of the proposed approach.The use of the repositioned concentration curve gives a constructed correlation that is much closer to the actual one.This study indicates the necessity to rearrange sensor-measured biomarker concentration vs time curves when correlations of concentration with sweating rate need to be constructed and proposes a practical point-by-point data repositioning strategy for doing so.The results presented here will benefit the study of sweat biomarkers with unclear correlations with sweating rate,as well as providing a basis for the development of more reliable sweat-based diagnostic methods. 展开更多
关键词 Wearable sweat monitoring Sweating rate Concentration rate correlation Timeline mismatch Machine learning
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A review of the experimental and numerical studies on the compression behavior of the additively produced metallic lattice structures at high and low strain rates
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作者 Muhammad Arslan Bin Riaz Mustafa Guden 《Defence Technology(防务技术)》 2025年第7期1-49,共49页
Recent advances in additive manufacturing have enabled the construction of metallic lattice structures with tailored mechanical and functional properties.One potential application of metallic lattice struc-tures is in... Recent advances in additive manufacturing have enabled the construction of metallic lattice structures with tailored mechanical and functional properties.One potential application of metallic lattice struc-tures is in the impact load mitigation where an external kinetic energy is absorbed by the deformation/crushing of lattice cells.This has motivated a growing number of experimental and numerical studies,recently,on the crushing behavior of additively produced lattice structures.The present study overviews the dynamic and quasi-static crushing behavior of additively produced Ti64,316L,and AlSiMg alloy lattice structures.The first part of the study summarizes the main features of two most commonly used additive processing techniques for lattice structures,namely selective-laser-melt(SLM)and electro-beam-melt(EBM),along with a description of commonly observed process induced defects.In the second part,the deformation and strain rate sensitivities of the selected alloy lattices are outlined together with the most widely used dynamic test methods,followed by a part on the observed micro-structures of the SLM and EBM-processed Ti64,316L and AlSiMg alloys.Finally,the experimental and numerical studies on the quasi-static and dynamic compression behavior of the additively processed Ti64,316L,and AlSiMg alloy lattices are reviewed.The results of the experimental and numerical studies of the dynamic properties of various types of lattices,including graded,non-uniform strut size,hollow,non-uniform cell size,and bio-inspired,were tabulated together with the used dynamic testing methods.The dynamic tests have been noted to be mostly conducted in compression Split Hopkinson Pressure Bar(SHPB)or Taylor-and direct-impact tests using the SHPB set-up,in all of which relatively small-size test specimens were tested.The test specimen size effect on the compression behavior of the lattices was further emphasized.It has also been shown that the lattices of Ti64 and AlSiMg alloys are relatively brittle as compared with the lattices of 316L alloy.Finally,the challenges associated with modelling lattice structures were explained and the micro tension tests and multi-scale modeling techniques combining microstructural characteristics with macroscopic lattice dynamics were recommended to improve the accuracy of the numerical simulations of the dynamic compression deformations of metallic lattice structures. 展开更多
关键词 Metallic lattice structures Additive manufacturing Strain rate sensitivity MICROSTRUCTURE Dynamic compression High strain rate loading MODELLING
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Growth rates of three common South Florida tree species affected by climate change and urbanization
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作者 Manuel Bernal-Escobar James HSpeer +1 位作者 Lauren Coombs Kenneth JFeeley 《Journal of Forestry Research》 2025年第5期90-102,共13页
South Florida’s natural forest ecosystems,including pine rocklands and hardwood hammocks,are threatened by land use change and urbanization,invasive species,and climate change.It is critical to understand the respons... South Florida’s natural forest ecosystems,including pine rocklands and hardwood hammocks,are threatened by land use change and urbanization,invasive species,and climate change.It is critical to understand the responses of these ecosystems to anthropogenic disturbances to conserve the remnants of the USA natural subtropical forests.Using dendrochronology,long-term growth patterns were characterized in three dominant native tree species:Bursera simaruba,Swietenia mahagoni,and Pinus elliottii.Core samples were collected from>30 individuals of each species in hardwood hammocks(B.simaruba and S.mahagoni)and pine rocklands(P.elliottii)to examine growth patterns.Relationships between annual tree growth rates and climatic variables were assessed to address three questions:(1)What are the climatic drivers of growth in these three South Florida tree species?(2)Are their growth rates stable or changing through time?and(3)Are tree growth rates affected by urbanization?Standardized growth rates of the three species have changed through time,with small young trees showing accelerated growth through time,whereas larger,older trees showed declining growth rates.S.mahagoni and B.simaruba grew faster in urbanized parks than in more natural parks,whereas P.elliottii grew slower in urban parks.There were positive correlations between tree growth and the current year’s fall precipitation and no discernable effects of the current year’s monthly temperatures on growth rates of any of the species.These results suggest that the foundational tree species of the southern USA endangered pine rocklands and hardwood hammocks may be vulnerable to ongoing changes in precipitation and temperature as well as other environmental effects associated with urbanization. 展开更多
关键词 SUBTROPICS Dendrochronology Growth rate changes Climate change URBANIZATION
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Pricing Multi-Strike Quanto Call Options on Multiple Assets with Stochastic Volatility, Correlation, and Exchange Rates
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作者 Boris Ter-Avanesov Gunter Meissner 《Applied Mathematics》 2025年第1期113-142,共30页
Quanto options allow the buyer to exchange the foreign currency payoff into the domestic currency at a fixed exchange rate. We investigate quanto options with multiple underlying assets valued in different foreign cur... Quanto options allow the buyer to exchange the foreign currency payoff into the domestic currency at a fixed exchange rate. We investigate quanto options with multiple underlying assets valued in different foreign currencies each with a different strike price in the payoff function. We carry out a comparative performance analysis of different stochastic volatility (SV), stochastic correlation (SC), and stochastic exchange rate (SER) models to determine the best combination of these models for Monte Carlo (MC) simulation pricing. In addition, we test the performance of all model variants with constant correlation as a benchmark. We find that a combination of GARCH-Jump SV, Weibull SC, and Ornstein Uhlenbeck (OU) SER performs best. In addition, we analyze different discretization schemes and their results. In our simulations, the Milstein scheme yields the best balance between execution times and lower standard deviations of price estimates. Furthermore, we find that incorporating mean reversion into stochastic correlation and stochastic FX rate modeling is beneficial for MC simulation pricing. We improve the accuracy of our simulations by implementing antithetic variates variance reduction. Finally, we derive the correlation risk parameters Cora and Gora in our framework so that correlation hedging of quanto options can be performed. 展开更多
关键词 Quanto Option Multi-Strike Option Stochastic Volatility (SV) Stochastic Correlation (SC) Stochastic Exchange rates (SER) CORA GORA Correlation Risk
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Effect of Application Rates and Base-Topdressing Ratios of Nitrogen and Potassium on the Yield and Quality of Flue-Cured Tobacco
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作者 SONG Yu WANG Ting +5 位作者 XIE Hui-ya ZHANG Yang ZHOU Yi LI Di-qin ZHENG Hua-bin LIU Zhao-wei 《Agricultural Science & Technology》 2025年第2期37-44,共8页
This study aimed to optimize the application rates and base-topdressing ratios of nitrogen and potassium for flue-cured tobacco in Chaling,Zhuzhou,Hunan.The tobacco variety‘Yunyan 87’was planted and subjected to eig... This study aimed to optimize the application rates and base-topdressing ratios of nitrogen and potassium for flue-cured tobacco in Chaling,Zhuzhou,Hunan.The tobacco variety‘Yunyan 87’was planted and subjected to eight different treatments with different application rates and base-topdressing ratios of nitrogen and potassium.The effect of different treatments on the agronomic traits,dry matter accumulation,yield,and quality of tobacco were compared.The results showed that the growth period of each treatment became shortened as the application rates of nitrogen and potassium decreased and as the base-topdressing ratios of nitrogen and potassium increased.The dry matter accumulation decreased with the reduction in the application rates of nitrogen and potassium.The yield and output value of T1 were the highest,reaching 2097.39 kg/hm^(2)and 65018.90 yuan/hm^(2),respectively,both significantly increasing by 57.5%compared with those of the control(CK).In addition,the proportions of leaves of high and mid-high grade in T1 were also the highest,reaching 73.31%and 88.79%,respectively,both higher than those of CK.The appearance evaluation results showed that the appearance quality scores of tobacco leaves of grades B2F and C3F in T1 were the highest,reaching 51 points,both of which were 3 points higher than that those of CK.All the treatments were consistent in terms of color,maturity,leaf structure,body,oil,and color intensity.Therefore,it was suggested that the tobacco production in Chaling should appropriately increase the proportions of nitrogen and potassium as base fertilizers on the basis of conventional fertilization,which was conducive to improving the yield and appearance quality of flue-cured tobacco. 展开更多
关键词 Flue-cured tobacco Application rates Base-topdressing ratios Yield Appearance quality
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Shortage of storage carbohydrates mainly determines seed abscission in Torreya grandis 'Merrillii'
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作者 Tao Liu Xiaolong Zhao +6 位作者 Guangxia Zhu Caoliang Jin Jingwei Yan Jinwei Suo Weiwu Yu Yuanyuan Hu Jiasheng Wu 《Horticultural Plant Journal》 2025年第2期619-632,共14页
Torreya grandis'Merrillii'is a well-known nut in South China with high nutritional value.Severe premature seed abscission limits the industrial development of T.grandis by causing serious economic losses.Howev... Torreya grandis'Merrillii'is a well-known nut in South China with high nutritional value.Severe premature seed abscission limits the industrial development of T.grandis by causing serious economic losses.However,the physiological mechanisms of seed abscission in T.grandis remain poorly understood.To gain insight into the relationships between carbohydrate status and seed abscission,three-year-old seed-bearing branches were taken as representative materials for the entire tree.Furthermore,the time course of changes in the photosynthetic rate and the non-structural carbohydrate(NSC)dynamics were monitored in the main sources(the one-year-old and two-year-old shoots),and the dry weight and NSC levels of sinks(the seeds,current female cone cluster,and current vegetative cluster)across all seed development stages were recorded.The cumulative seed abscission rate significantly increased,reaching 91.5%from 0 to 72 days after seed protrusion time(SPT).NSC levels in the main sources significantly decreased by 56%-79%,accompanied by a significantly increased photosynthesis rate of 17.1%-49.1%during that period and increased NSC levels in the three sinks.The gene expression level of cell wall invertase(TgCWIN)was significantly correlated with sucrose,fructose,and glucose levels.The carbon storage capacity of the main sources significantly decreased from 6.03 to3.14 mmol C·d^(-1),with a stable photosynthetic capacity,from 0 to 72 days after SPT,whereas the carbon demand of the three sinks showed a continuously increasing trend from 3.14 to 7.71 mmol C·d^(-1).In addition,sucrose supplementation significantly decreased the cumulative seed abscission rate.These results suggest that storage carbohydrates play a major role in the regulatory mechanism of seed abscission in T.grandis.Our study provides a theoretical basis for improving T.grandis yield through establishing a better carbon balance between sources and sinks using timely fertilization or proper pruning procedures. 展开更多
关键词 Storage carbohydrates Seasonal photosynthetic rate Non-structural carbohydrates Seed abscission
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Influence of life-history traits on mitochondrial DNA substitution rates exceeds that of metabolic rates in teleost fishes
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作者 Yangyang Jing Rui Long +5 位作者 Juanzhu Meng Ya Yang Xinyi Li Bairu Du Ayesha Naeem Yiping Luo 《Current Zoology》 2025年第3期284-294,共11页
Understanding the molecular relevance of metabolic rate(MR)is crucial for unveiling the mechanisms driving the evolution of animals.In this study,we investigated the association between mitochondrial DNA characteristi... Understanding the molecular relevance of metabolic rate(MR)is crucial for unveiling the mechanisms driving the evolution of animals.In this study,we investigated the association between mitochondrial DNA characteristics and both resting and maximal MRs in conjunction with life-history traits among 139 species of teleost fish,We gathered fish MR data from various sources and procured sequences of 13 mitochondrial protein-encoding genes.We calculated the absolute substitution rate for entire nucleotide sequences and 4-fold degenerate sites of each gene,along with encoding amino acid sequences.Using the phylogenetic comparative method,we then explored the associations between MR and mitochondrial DNA absolute substitution rate.Additionally,we screened MR-associated single nucleotide variants in mitochondrial DNA.The findings indicate no positive correlation between MRs and any substitution rate values of both combined sequences and individual mitochondrial protein-coding genes,refuting the MR hypothesis.Instead,both maximum body size and longevity correlated negatively with molecular substitution rates,suggesting their influences on both mutation and fixation within mitochondrial genes in fish.Results also revealed significant correlations between base variation at ATP6_169 and both resting MR and maximum MR,identifying the unique ATP6_169G in Scombridae fish,which results in an extremely low isoelectric point(pl)value of the ATP6 protein.Considering its functional significance,the ATP6_169G in Scombridae fish might link to their lifestyle characterized by fast locomotion and high metabolic demands alongside a slower molecular evolutionary rate. 展开更多
关键词 FISH metabolic rate mitochondrial genes substitution sites single nucleotide variant
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Enhancing adenoma detection rates:The case for upgrading to advanced colonoscopy technology
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作者 Eyad Gadour 《World Journal of Gastrointestinal Endoscopy》 2025年第9期158-160,共3页
A recent study by Nishizawa et al presented significant findings regarding the advantages of next-generation colonoscopes,specifically the CF-XZ1200 and CFEZ1500 models,in enhancing the adenoma and sessile serrated le... A recent study by Nishizawa et al presented significant findings regarding the advantages of next-generation colonoscopes,specifically the CF-XZ1200 and CFEZ1500 models,in enhancing the adenoma and sessile serrated lesion detection rates.As colorectal cancer remains a leading cause of cancer-related mortality globally,the implications of improved detection rates are substantial.This letter advocated the adoption of advanced colonoscopy technology,emphasizing the robust methodology of the study,including propensity score matching,which enhanced the validity of its conclusions.Notable improvements in image quality,facilitated by innovations such as 4 K resolution and texture enhancement imaging,enable endoscopists to identify even the smallest lesions,ultimately leading to improved patient outcomes.Given the compelling evidence presented,it is imperative for healthcare institutions to prioritize the integration of these advanced scopes into routine practice to enhance screening efficacy and reduce the burden of colorectal cancer. 展开更多
关键词 COLONOSCOPY Adenoma detection rate Advanced technology Image enhancement Colorectal cancer
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Survival Rates and Molecular Responses of Diploid and Triploid Pacific Oysters Crassostrea gigas Under Different Salinity and Temperature Conditions
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作者 SUN Lingling JIANG Gaowei +1 位作者 XU Chengxun LI Qi 《Journal of Ocean University of China》 2025年第4期1121-1129,共9页
Triploid oysters are widely cultured due to their superior growth compared to diploids.However,differences in tempera-ture-salinity adaptation between di-and triploid oysters remain inconclusive.This study compared th... Triploid oysters are widely cultured due to their superior growth compared to diploids.However,differences in tempera-ture-salinity adaptation between di-and triploid oysters remain inconclusive.This study compared the survival rates,antioxidant en-zyme activities,and gene expressions in di-and triploid Pacific oyster Crassostrea gigas cultured in different temperatures(17,20,23,26,and 29℃)and salinities(18,22,26,30,and 34).Results showed that the optimum survival condition for both di-and triploids is 23℃/30.At 23℃,triploids exhibited significantly higher superoxide dismutase activity and lower heat shock protein 70(Hsp70)expression than diploids.At 29℃,triploids exhibited significantly higher survival rates than diploids.Across varying tem-peratures,triploids demonstrated significantly higher survival rates and antioxidant enzyme activities,along with lower malondialdehyde(MDA)levels and Hsp70 expression compared to diploids.The overall results demonstrate that triploids have a more robust antioxidant ca-pacity,reduced oxidative damage,and lower mortality than diploids under temperature treatments.Additionally,at a salinity of 18,triploids showed significantly higher catalase(CAT)level than diploids.Across varying salinities,triploids maintained lower MDA levels.These results suggest that triploids possess a stronger antioxidant defense under salinity treatments.In conclusion,triploid C.gigas demonstrates superior adaptation to diverse temperature and salinity conditions over diploids and are recommended for culture to improve oyster production. 展开更多
关键词 Crassostrea gigas temperature-salinity adaptation di-and triploid survival rate molecular response
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Comparison of complication rates after early and late closure of loop ileostomies:A retrospective cohort study
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作者 PırıltıÖzcan Özgül Düzgün 《World Journal of Gastrointestinal Surgery》 2025年第8期124-132,共9页
BACKGROUND In the treatment of rectal cancer,a temporary loop ileostomy(TLI)is created after low anterior resection to protect bowel function in the postoperative period.Dehydration and kidney failure are significant ... BACKGROUND In the treatment of rectal cancer,a temporary loop ileostomy(TLI)is created after low anterior resection to protect bowel function in the postoperative period.Dehydration and kidney failure are significant potential complications in loop ileostomies.Compared to late closure(3-6 months),early closure(10-14 days)of the TLI may facilitate faster patient recovery and shorter hospital stays.AIM To compare early and late closure of TLIs and demonstrate that early stoma closure can be performed without increasing morbidity.METHODS This study included patients who underwent TLI for rectal cancer,with data collected prospectively between June 2016 and October 2024 and analyzed retrospectively.Patients whose stomas were closed in the late period(3-6 months)between June 2016 and October 2022(group A)were compared with those who underwent early closure(10-14 days)between October 2022 and 2024(group B),with the primary outcome being complication rate and the secondary outcome being quality of life.RESULTS A total of 270 TLIs were created(70.9%).Of these,120(44.4%)were closed in the late period(group A),and 150(55.6%)were closed in the early period(group B).There was no statistically significant difference between group A and group B in terms of demographic and clinicopathological characteristics(P>0.05).Perioperative(anesthesia management,operative time,blood loss,surgical technique)and postoperative findings(anastomotic leak,infection)were similar between the two groups and were not statistically significant(P>0.05).There were no statistically significant differences in complication rates as the primary outcome between the two groups.Quality of life as a secondary outcome was significantly higher in the early closure group(P<0.05).CONCLUSION No statistically significant difference was found between early and late loop ileostomy closure in terms of perioperative and postoperative morbidity.Early closure accelerated patients’psychological and social recovery. 展开更多
关键词 Rectum cancer Loop ileostomy Early period Late period Complication rates
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Microstructural evolution and comprehensive properties of Mg-8Li-3Al-2Zn alloy during annealing treatment under various cooling rates
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作者 Ling Li Wang-yang Xue +3 位作者 Zhu-min Li Tian-yu Liu Rui Zheng Guo-bing Mao 《China Foundry》 2025年第4期417-426,共10页
Annealing treatment is an effective strategy to enhance the comprehensive properties of Mg-8Li-3Al-2Zn(LAZ832)alloy,where the cooling rate plays a decisive role in tailoring microstructure and performance.This study s... Annealing treatment is an effective strategy to enhance the comprehensive properties of Mg-8Li-3Al-2Zn(LAZ832)alloy,where the cooling rate plays a decisive role in tailoring microstructure and performance.This study systematically investigates the effects of cooling rates,controlled via water quenching(WC),air cooling(AC),and furnace cooling(FC),on the phase evolution,mechanical properties,and corrosion resistance of LAZ832.The annealed microstructure consists ofα-Mg,β-Li,AlLi,and MgLi_(2)Al phases,and the volume fraction of Al-Li phases(AlLi and MgLi_(2)Al)increases as the cooling rate decreases.Strengthening mechanisms are dominated by solid solution strengthening,driven by the dissolution of Al and Zn atoms into the matrix,which significantly enhances tensile strength.However,excessive solute content leads to a marked decline in ductility.Scanning probe microscope(SPM)reveals an elevated work function due to the dissolution of Al and Zn atoms into the matrix phase,correlating with improved corrosion resistance.Comprehensive analysis demonstrates that air cooling achieves an optimal balance between tensile strength,ductility,and corrosion resistance,outperforming furnace-cooled samples and offering a pragmatic compromise compared to water-quenched specimens with higher strength but brittle failure.These findings establish a robust framework for designing LAZ832 alloys with tailored microstructures and multi-property optimization,advancing their application in lightweight engineering fields. 展开更多
关键词 Mg-Li-Al-Zn alloy mechanical properties corrosion resistance work function cooling rate
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Effect of comprehensive perioperative nursing on pain intensity,complication rates,and comfort levels in patients undergoing gallstone surgery
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作者 Chen-Yan Bao Xiao-Kun Ding +2 位作者 Qiao-Fei Qi Peng Ye Ze-Jun Fang 《World Journal of Gastrointestinal Surgery》 2025年第2期111-119,共9页
BACKGROUND Surgery is the gold standard for gallstone treatment.Nevertheless,the complications associated with the surgical procedure can exert diverse and adverse impacts on patients’health and quality of life to va... BACKGROUND Surgery is the gold standard for gallstone treatment.Nevertheless,the complications associated with the surgical procedure can exert diverse and adverse impacts on patients’health and quality of life to varying extents.Hence,it is essential to offer perioperative care to patients undergoing gallstone surgery.AIM To examine the impact of perioperative comprehensive nursing on pain intensity,complication rates,and patient comfort in individuals undergoing gallstone surgery.METHODS From February 2022 to February 2024,195 patients who underwent gallstone surgery at Sanmen People’s Hospital were selected and divided into two groups:A control group receiving routine nursing care(95 patients)and a research group receiving perioperative comprehensive nursing(100 patients).Key postoperative recovery indicators,including time to first postoperative anal exhaust,oral food intake,and ambulation,were observed,along with pain intensity(measured by the numeric rating scale),complication rate(bleeding,incision infection,recurrence),patient comfort(assessed using the visual analogue scale),and quality of life(measured by the World Health Organization Quality of Life-BREF).RESULTS The research group showed significantly shorter times to first postoperative anal exhaust,oral intake,and ambulation.Moreover,numeric rating scale pain scores in the research group were markedly lower post-nursing,and the total complication rate was significantly reduced compared to the control group.Furthermore,comfort levels improved considerably in the research group,and World Health Organization Quality of Life-BREF scores across the physical,psychological,social,and environmental domains were significantly higher compared to the control group following nursing care.CONCLUSION Perioperative comprehensive nursing effectively enhances postoperative recovery in patients undergoing gallstone surgery,reducing pain,lowering complications,and improving patient comfort and quality of life,which deserves clinical application. 展开更多
关键词 Perioperative comprehensive nursing Gallstone surgery Pain intensity Complication rate COMFORT
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Mechanical behavior of GH4720Li nickel-based alloy at intermediate temperature for different strain rates
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作者 Xiao-can Wen Xin-yu Meng +4 位作者 Shao-min Lyu Xing-fei Xie Zhi-qiang Luo Jing-long Qu Jin-hui Du 《Journal of Iron and Steel Research International》 2025年第7期2163-2171,共9页
The GH4720Li alloy is one of the most widely used precipitation-strengthened nickel-based superalloy.However,systematic study about effect of strain rate on the plastic deformation behavior of GH4720Li alloy at interm... The GH4720Li alloy is one of the most widely used precipitation-strengthened nickel-based superalloy.However,systematic study about effect of strain rate on the plastic deformation behavior of GH4720Li alloy at intermediate temperature is lacking.The evolution of the tensile properties and plastic deformation mechanism of GH4720Li alloy with the strain rate at 650℃ were systematically studied with the help of transmission electron microscopy analysis.The results show that the tensile strength of the alloy increases and the plasticity decreases with the increase in strain rate.When the strain rate is 5 min^(-1),the tensile strength of the alloy is 1448 MPa and the tensile plasticity is 18%.As the strain rate increases from 0.05 to 0.5 min^(-1),the size and morphology of the primaryγ′phase of the alloy remain unchanged,with an average size of about 1.8μm.However,when the strain rate further increases to 5 min^(-1),the average size of the primaryγ′phase increases to 2.5μm.In addition,the increase of strain rate has no significant effect on the size and distribution of secondary and tertiaryγ′phases.As the strain rate increases from 0.05 to 5 min^(-1),the deformation mechanism of alloy gradually evolved from dislocation slip and twin to dislocation slip,indicating that the plastic deformation mechanism of the alloy presents a high strain rate sensitivity at 650℃. 展开更多
关键词 Nickel-based superalloy Strain rate Tensile property Plastic deformation mechanism TWINNING
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